The Go standard library and subrepos were a good place to start because it's many, many Go packages all covered by a single issue tracker. The signal to noise ratio (i.e., issues with proper foo/bar: prefixes) was high. So it's where most of the value lies.

Supporting 3rd party packages would be quite hard, but it's not completely off the table. And if/when github repos are supported, supporting vanity import paths that are pointing at github would be very easy.

It seems silly they've posted that post on the blog which isn't accessible to the target demographic...

The post is short, I'll paste it here for convenience:

Hello, 中国!
22 January 2018

We are thrilled to announce that the content on golang.org is now available in mainland China through the name https://golang.google.cn. The growing Go developer community in China can now directly access official documentation, technical articles, and binaries.

The Go community in China is bigger than ever. In 2015, Robert Griesemer visited Shanghai to attend GopherChina, the first Go conference in the country. In the years since, it has become one of the largest Go conferences in the world with over 1200 attendees at their 2017 event. Over the same period, one of the most popular community-built Go forums saw their traffic increase threefold and the number of participants in Go-specific groups on social platforms like WeChat and QQ has grown to over 11,000 people.

Go adoption within China-based companies has also increased, with Qiniu, Huawei, Alibaba, and countless others using Go heavily in their production stacks.

We’re excited to provide even more resources for Go developers in China to supplement the excellent material already available to them, but this is just the beginning. We’ll be focusing on making Go more accessible to non-English speakers in 2018, so keep watching this space.